threadpool

问题 I need a threadpool for my application, and I'd like to rely on standard (C++11 or boost) stuff as much as possible. I realize there is an unofficial(!) boost thread pool class, which basically solves what I need, however I'd rather avoid it because it is not in the boost library itself -- why is it still not in the core library after so many years? In some posts on this page and elsewhere, people suggested using boost::asio to achieve a threadpool like behavior. At first sight, that looked

问题 I need a threadpool for my application, and I'd like to rely on standard (C++11 or boost) stuff as much as possible. I realize there is an unofficial(!) boost thread pool class, which basically solves what I need, however I'd rather avoid it because it is not in the boost library itself -- why is it still not in the core library after so many years? In some posts on this page and elsewhere, people suggested using boost::asio to achieve a threadpool like behavior. At first sight, that looked

问题 I read many articles said that async/await doesn't create additional threads. But the message from Output and Thread windows in debug mode of Visual Studio said the contrary. I created a very simple example windows form with some code; private void button2_Click(object sender, EventArgs e) { Task t = methodAsync(); //t.Wait(); } async Task methodAsync() { Console.WriteLine($"==before DownloadStringTaskAsync"); using (var wc = new System.Net.WebClient()) { string content = await wc

问题 I need to run a function int f(int i) with 10_000 parameters and it takes around 1sec to execute due to I/O time. In a language like Python, I can use threads (or async/await , I know, but I'll talk about it later) to parallelize this task. If I want to always have 10 running threads, and to split the task between them, I can use ThreadingPool : def f(p): x = [...] return x p = ThreadPool() xs = p.map(f, range(10_000)) But how does it work ? If I want to implement a similar thing with, let's

问题 I use ScheduledExecutorService in my application. I need to use it from time to time in certain Utility class to run scheduled threads. Is it a good design to hold ScheduledExecutorService in static field? Is it a must to invoke ScheduledExecutorService.shutdown() in such case? What is the risk if I do not invoke shutdown? That's what I thought to do: private static ScheduledExecutorService exec = Executors.newScheduledThreadPool(5); public void scheduleTask(String name) { Future<?> future =

问题 I have a List with items that I want to download. I use a for Loop to iterate the list. For each item in this List I start a new Thread that references the item. My Problem is that I want limit the maxDownload at the same time. for (int i = downloadList.Count - 1; i >= 0; i--) { downloadItem item = downloadList[i]; if (item.Status != 1 && item.Status != 2) { ThreadStart starter = delegate { this.DownloadItem(ref item); }; Thread t = new Thread(starter); t.IsBackground = true; t.Name = item

问题 I got very confused by reading Thread Pooling. I learnt the concept, how they actually works. But I confused in the part , how to code this. I searched a lot on the net. Finally I got a blog, that have codes , given below, CONDITION IS, NOT TO USE IN-BUILT CLASS Code 1 public class ThreadPool { private BlockingQueue taskQueue = null; private List<PoolThread> threads = new ArrayList<PoolThread>(); private boolean isStopped = false; public ThreadPool(int noOfThreads, int maxNoOfTasks){

问题 I am trying to implement thread pool in C++ using pthread. I want to encapsulate logic related to threads management in one object which is taking ownership of these threads. That means whenever this object is destroyed, threads must be stopped and cleaned up. I've been testing my code and it turns out that I get segmentation fault when I destroy WorkerThreadManager object while there is boost::function called. See the code and backtrace from GDB. I don't really understand why it happens, as

问题 I can't figure out what to use for scheduling and pooling runnables of different state (each Runnable instance has different state). I could use ScheduledExecutorFactoryBean together with MethodInvokingRunnable to supply arguments. But take a look at the key ScheduledExecutorFactoryBean method, it is designed in a way that all task should start at the beginning. protected void registerTasks(ScheduledExecutorTask[] tasks, ScheduledExecutorService executor) { for (ScheduledExecutorTask task :

问题 I use ThreadPool.QueueUserWorkItem for creating a thread on Windows CE (I use .NET Framework 3.5). Sometimes the thread waits for something and starts too late. In the QueueUserWorkItem documentation it says that the delegate will be executed "when a thread pool thread becomes available". Is there a way to force the ThreadPool to execute my delegate immediately? Would Thread.Start() be a solution for this? Thank you! 回答1: First off, QueueUserWorkItem doesn't create a thread, it merely places